CDRIVER-2699 don't retry WriteConcernFailed error

Error code 64, "WriteConcernFailed", is no longer a retryable write.
If commitTransaction returns error code 64, add the error label
"UnknownTransactionCommitResult".

Author: ajdavis

src/libmongoc/src/mongoc/mongoc-client-session.c

@@ -121,6 +121,7 @@ txn_finish (mongoc_client_session_t *session,
    bson_error_t err_local;
    bson_error_t *err_ptr = error ? error : &err_local;
    bson_t reply_local = BSON_INITIALIZER;
+   mongoc_write_err_type_t error_type;
    bool r = false;
 
    _mongoc_bson_init_if_set (reply);
@@ -151,19 +152,23 @@ txn_finish (mongoc_client_session_t *session,
 
    /* Transactions Spec: "Drivers MUST retry the commitTransaction command once
     * after it fails with a retryable error", same for abort */
+   error_type = _mongoc_write_error_get_type (&reply_local);
    if (!r && (err_ptr->domain == MONGOC_ERROR_STREAM ||
-              _mongoc_write_is_retryable_error (&reply_local))) {
+              error_type == MONGOC_WRITE_ERR_RETRY)) {
       bson_destroy (&reply_local);
       r = mongoc_client_write_command_with_opts (
          session->client, "admin", &cmd, &opts, &reply_local, err_ptr);
+
+      error_type = _mongoc_write_error_get_type (&reply_local);
    }
 
    /* Transactions Spec: "add the UnknownTransactionCommitResult error label
     * when commitTransaction fails with a network error, server selection
     * error, or write concern failed / timeout." */
    if (intent == TXN_COMMIT && reply) {
       if (!r && (err_ptr->domain == MONGOC_ERROR_STREAM ||
-                 _mongoc_write_is_retryable_error (&reply_local))) {
+                 error_type == MONGOC_WRITE_ERR_RETRY ||
+                 error_type == MONGOC_WRITE_ERR_WRITE_CONCERN)) {
          bson_copy_to_excluding_noinit (
             &reply_local, reply, "errorLabels", NULL);
          copy_labels_plus_unknown_commit_result (&reply_local, reply);

src/libmongoc/src/mongoc/mongoc-client.c

@@ -1555,8 +1555,9 @@ _mongoc_client_retryable_write_command_with_stream (
     * a new writable stream and retry. If server selection fails or the selected
     * server does not support retryable writes, fall through and allow the
     * original error to be reported. */
-   if (!ret && is_retryable && (error->domain == MONGOC_ERROR_STREAM ||
-                                _mongoc_write_is_retryable_error (reply))) {
+   if (!ret && is_retryable &&
+       (error->domain == MONGOC_ERROR_STREAM ||
+        _mongoc_write_error_get_type (reply) == MONGOC_WRITE_ERR_RETRY)) {
       bson_error_t ignored_error;
 
       /* each write command may be retried at most once */

src/libmongoc/src/mongoc/mongoc-collection.c

@@ -3325,8 +3325,9 @@ mongoc_collection_find_and_modify_with_opts (
     * a new writable stream and retry. If server selection fails or the selected
     * server does not support retryable writes, fall through and allow the
     * original error to be reported. */
-   if (!ret && is_retryable && (error->domain == MONGOC_ERROR_STREAM ||
-                                _mongoc_write_is_retryable_error (reply_ptr))) {
+   if (!ret && is_retryable &&
+       (error->domain == MONGOC_ERROR_STREAM ||
+        _mongoc_write_error_get_type (reply_ptr) == MONGOC_WRITE_ERR_RETRY)) {
       bson_error_t ignored_error;
 
       /* each write command may be retried at most once */

src/libmongoc/src/mongoc/mongoc-write-command-private.h

@@ -92,6 +92,14 @@ typedef struct {
 } mongoc_write_result_t;
 
 
+typedef enum {
+   MONGOC_WRITE_ERR_NONE,
+   MONGOC_WRITE_ERR_OTHER,
+   MONGOC_WRITE_ERR_RETRY,
+   MONGOC_WRITE_ERR_WRITE_CONCERN,
+} mongoc_write_err_type_t;
+
+
 const char *
 _mongoc_command_type_to_field_name (int command_type);
 const char *
@@ -212,8 +220,8 @@ _mongoc_write_result_destroy (mongoc_write_result_t *result);
 void
 _append_array_from_command (mongoc_write_command_t *command, bson_t *bson);
 
-bool
-_mongoc_write_is_retryable_error (const bson_t *reply);
+mongoc_write_err_type_t
+_mongoc_write_error_get_type (const bson_t *reply);
 
 BSON_END_DECLS
 

src/libmongoc/src/mongoc/mongoc-write-command.c

@@ -560,6 +560,7 @@ _mongoc_write_opmsg (mongoc_write_command_t *command,
 
       if (ship_it) {
          bool is_retryable = parts.is_retryable_write;
+         mongoc_write_err_type_t error_type;
 
          /* Seek past the document offset we have already sent */
          parts.assembled.payload = command->payload.data + payload_total_offset;
@@ -589,9 +590,9 @@ _mongoc_write_opmsg (mongoc_write_command_t *command,
           * select a new writable stream and retry. If server selection fails or
           * the selected server does not support retryable writes, fall through
           * and allow the original error to be reported. */
-         if (!ret && is_retryable &&
-             (error->domain == MONGOC_ERROR_STREAM ||
-              _mongoc_write_is_retryable_error (&reply))) {
+         error_type = _mongoc_write_error_get_type (&reply);
+         if (!ret && is_retryable && (error->domain == MONGOC_ERROR_STREAM ||
+                                      error_type == MONGOC_WRITE_ERR_RETRY)) {
             bson_error_t ignored_error;
 
             /* each write command may be retried at most once */
@@ -1430,13 +1431,14 @@ _mongoc_write_result_complete (
    RETURN (!result->failed && result->error.code == 0);
 }
 
-bool
-_mongoc_write_is_retryable_error (const bson_t *reply)
+
+mongoc_write_err_type_t
+_mongoc_write_error_get_type (const bson_t *reply)
 {
    bson_error_t error;
    if (_mongoc_cmd_check_ok_no_wce (
           reply, MONGOC_ERROR_API_VERSION_2, &error)) {
-      return false;
+      return MONGOC_WRITE_ERR_NONE;
    }
 
    switch (error.code) {
@@ -1447,17 +1449,18 @@ _mongoc_write_is_retryable_error (const bson_t *reply)
    case 13436: /* NotMasterOrSecondary */
    case 189:   /* PrimarySteppedDown */
    case 91:    /* ShutdownInProgress */
-   case 64:    /* WriteConcernFailed */
    case 7:     /* HostNotFound */
    case 6:     /* HostUnreachable */
    case 89:    /* NetworkTimeout */
    case 9001:  /* SocketException */
-      return true;
+      return MONGOC_WRITE_ERR_RETRY;
+   case 64: /* WriteConcernFailed */
+      return MONGOC_WRITE_ERR_WRITE_CONCERN;
    default:
       if (strstr (error.message, "not master") ||
           strstr (error.message, "node is recovering")) {
-         return true;
+         return MONGOC_WRITE_ERR_RETRY;
       }
-      return false;
+      return MONGOC_WRITE_ERR_OTHER;
    }
 }